What is clear is that when looking at the two maps side by side, countries with the most pious citizens are not the least corrupt; in fact, when you remove communist or formerly communist countries, which have their own complex histories of corruption and state intervention in religion, it’s very nearly the opposite.

More religious countries appear to be more corrupt. (More rigorous examinations also bear out this conclusion, as do studies that look at legislation of religion as well as just personal practice –Heather Marquette at the University of Birmingham gives a good summary of the field.)

This does not mean that religiosity causes corruption – many studies have tried to establish a causal link, with frustratingly ambiguous and contradictory conclusions.

However, it does mean that religious movements or political parties that claim the evils of corruption can be eradicated by making society more religious are engaging in wishful thinking or outright deception.

To put it more bluntly, Islam is not the solution.

(Nor, for that matter, is any other religion. Check out the corruption scores of devoutly Catholic nations.)

Claims that a government ruled by people who fear god and pray every day will automatically be more honest than one run by secularists or atheists fly in the face of empirical evidence.

Australia, whose prime minister is an atheist, is consistently among Transparency International’s highest scorers, as are profoundly non-religious Scandinavian countries; highly religious societies, like Afghanistan and Somalia are at the bottom.

It’s not random chance that societies like Australia or the Scandinavian countries, which combine with low religiosity and low levels of corruption, also have some of the world’s highest standards of living.

Both corruption and religiosity are strongly related to low scores on measures of wellbeing like per capita income and the Human Development Index. Again, proving causation is nearly impossible. But it’s safe to say that countries that are wealthy, have little public corruption, and provide their citizens with high-quality social services like healthcare and education are unlikely to be highly religious.

This presents an interesting conundrum for politicians like the Freedom and Justice Party, who promise voters both good governance and more religion in public and private life. There’s scant evidence that the two goals are compatible.

Realistically speaking, the most likely explanation for the Muslim Brotherhood’s dismal economic record lies in a combination of inexperience and incompetence on the part of the new regime, the deeply entrenched corrupt and corporatist legacy of the old regime, and global economic malaise. Secular governments can of course be corrupt, as those who lived under Mubarak or Putin are well aware.

Nonetheless, the relationship between religiosity and corruption does suggest a fun conspiracy theory to explain why the government seems to consistently make the worst possible choices for the economy: Perhaps the Ikhwan and their Salafist fellow travelers are well aware that a society that is poor, corrupt, uneducated, and unhealthy is also more likely to embrace religious fundamentalism, and this is all part of a phenomenally complex and masterfully subtle master plan.